Antenna tuner units (ATUs) are employed in user equipment (UE) such as mobile terminals in order to maintain good link quality between base transceiver stations (BTSs) and the UE. In particular, an ATU is usable to match antenna input impedance with the output impedance of a power amplifier (PA). ATUs are especially useful when the UE is a mobile terminal communicating with a BTS, since the antenna of the mobile terminal can experience voltage standing wave ratio (VSWR) changes that may range from near 1:1 to 3.5:1 as the position of the antenna relative to the user's body changes. For example, antenna input impedance often experiences relatively large changes as portions of the user's body move within the near field of the antenna. These relatively large antenna input impedance changes typically result in a large reflected power, which limits the total radiated power (TRP) to less than a desired maximum amount of TRP.
Unreliable power control due to antenna impedance fluctuations is problematic for third generation (3G) and fourth generation (4G) UEs such as mobile terminals because standards for 3G and 4G UE include relatively strict power control accuracy constraints. What is needed is a UE antenna tuner control system and methods that utilize a BTS inner power control loop, and in particular utilize a Node-B inner power control loop.